Ventilating attachment



y 1956 M. E. ROBERTSON 2,

VENTILATING ATTACHMENT Filed Jan. 12, 1955 2 Sheets-Sheet 1 INVENTOR.MEAD E. ROBERTSON y 1, 1956 M. E. ROBERTSON 2,756,564

VENTILATING ATTACHMENT Filed Jan. 12, 1955 2 Sheets-Sheet 2 MEAD E.ROBERTSON BY 04?. My

Attorney United States Patent VENTILATING ATTACHMENT Mead E. Robertson,Stoughton, Wis.

Application January 12, 1955, Serial No. 481,401

13 Claims. (Cl. 62-102) This invention relates to a ventilatingattachment for a cooling device and more particularly to means forenhancing the efiiciency obtained with flat plate vehicle cooling unitswhich comprises an attachment which does not cover either of the facesthereof and which is disposed along a horizontal edge thereof.

Flat plate cooling units are conveniently used in obtaining andmaintaining low temperatures in the bodies of vehicles such as trucksand railroad cars which are adapted to contain perishables such as dairyproducts, produce and meats, frozen food, ice cream, frozen confections,and the like. Normally such units are disposed on the walls of abox-like body or may be disposed on walls or partitions of the bodies orpartitions themselves. In some installations they may be disposedhorizontally on either the ceiling or floor of the compartment. In anysuch arrangement the cooling of the goods contained in the compartmenthas been characterized by being carried out in any one of severalmanners. In the first, cooling is by conduction for those goods piledagainst the refrigerant plates and by radiant heat absorption orunassisted conduction cooling for goods located nearer the center of thecompartment. In the second, conduction cooling is assisted by coolingwith'fans or blowers suitably located in the compartment to force warmerair against the plates and to bring air cooled by the plates into moreintimate contact with the goods contained in the compartment. Suchsystems of course have the advantage that turbulence of the air isincreased with resultant increase in heat transfer. In the thirdarrangement cooling is primarily accomplished with a forced draftarrangement; the cooling unit is shrouded; the blower or fan pulls airthrough the shroud or housing surrounding the cooling element, thusforcing cool air into the compartment containing goods being maintainedunder refrigeration and pulling warm air from the compartment into andthrough the housing and into relatively intimate contact with thecooling unit. Each of these methods has certain disadvantages. Theefl'iciency of installations utilizing unassisted conduction cooling isextremely low when goods nearly fill the compartment because freecirculation of air is nearly entirely impeded and conductive cooling ofgoods near the center of the compartment is extremely slow. The same isgenerally true of the as sisted conduction cooling arrangements. Whenthe compartment is full of goods the fan usually circulates air in onlya small portion, often the upper part, of the compartment and itsefficiency is enormously reduced. Thus in order to obtain adequaterefrigeration with such a system when the compartment is fully loaded itis generally necessary to keep the fan going all the time. This resultsin a considerable load on the electrical system of the vehicle on whichthe compartment is mounted. In a forced draft installation it isnecessary to keep the fan going all of the time in order to obtain anyeffective cooling. 7

Each of these installations is particularly ineffective when arefrigerated truck must be loaded with goods ice . 2 such as dairyproducts in the evening in order to be ready to start out early in themorning and must be dependent on the truck refrigerating system tomaintain the necessary low temperature throughout the night. Therequirements of such a cooling system are that it be capable.

of high capacity at certain times such as immediately after the goodsare loaded until they are refrigerated to the necessary low temperaturerequired for storage and at times when the truck is in use makingdeliveries and the doors are being opened at frequent intervals. On theother hand it must be capable of cooling at a very low rate of capacitywith extremely high efiiciency over long periods of time during whichthe truck is standing and not in use in order to prevent destruction ofthe trucks battery during such periods. In short, it is impracticable todrive a fan or blower off a trucks electrical system for long periods oftime when the truck is unattended and its engine is not running but uponother occasions it is necessary that the refrigerating system of thetruck have a high capacity with a high efliciency, utilizing arelatively powerful blower, in order to maintain the degree ofrefrigeration necessary for proper storage. During such periodsgenerally the truck is attended and its motor is running but anunassisted conduction system which is quite satisfactory for longperiods of unattended storage is entirely inadequate for use at suchtimes.

My invention provides an assisted conduction arrangement which is farmore efiicient than those of the prior art and which permits a low rateof refrigeration to be maintained over long periods of time with aminimum load on the trucks electrical-system and yet permits a high rateof refrigeration to be obtained at certain times, or with a minimum ofexpense.

It is therefore an object of this invention to provide means mountablewithin a low temperature storage cabinet carried by a vehicle andadapted to be attached to a flat refrigerating plate, for obtainingimproved refrigerating efficiency .during periods of both low demand andhigh demand.

Another object is a device for attachment to one of the horizontal edgesof a refrigerating plate, which is adapted to provide forced draftrefrigeration during periods of high demand and to provide unassistedconduction and radiation cooling during periods of low demand.

Further objects will become apparent from the drawings and the followingdetailed description in which it is my intention to clearly set forthand describe my invention and to show its applicability without limitingits scope. In the drawings and description like reference numerals referto like parts and:

Figure 1 is a partially cutaway perspective view of one embodiment of myinvention installed in a refrigerated compartment mounted on a truck;

Figure 2 is a partially cutaway perspective view of a preferredembodiment of the device of my invention applied to the bottom edge of arectangular refrigerating plate, the device being cross-sectioned onlines 2 as shown in Figure 3;

Figure 3 is a cross-sectional view of the device taken at right anglesto the bottom edge of the rectangular refrigerating plate;

Figure 4 is a partially cutaway perspective view of another embodimentof the device, the device being crosssectioned on lines 4-4 as shown inFigure 5;

Figure 5 is a cross-sectional view of the device taken on a plane normalto the surfaces of the rectangular refrigerating plate; and

Figure 6 is a partially cutaway perspective view of a truck with arefrigerated compartment mounted thereon and provided with analternative installation of the device of the invention.

Referring now to Figures 1, 2 and 3 there is shown a truck 1 having acompartment 2 mounted thereon which is adapted to be refrigerated byrefrigerating plate 3.

The device of the invention is disposed along the lower edge ofrefrigerating plate 3 and comprises a central trough-like portion 5provided with plenum chambers 6 at each end thereof communicatingtherewith. Air which flows downwardly along the faces of plate 3 iscollected in trough-like portion 5, sucked into plenum chambers 6 andthence upward through ducts 7 by fan or blower 8 which thereupon blowsthe cool air thus collected out over the contents of the body anddownward as shown by arrows 9 into intimate contact with the contents 10contained in said compartment. Trough-like portion 5 comprises apartition member 15, two upwardly extending partitions 16 on oppositesides thereof substantially parallel thereto and at their top edgesspaced away from plate 3 as shown at 17, thus defining channels 18. Oneach side of channels 18 are channels 19 defined by bottom 2% upwardlyextending Walls 21 and inwardly extending roof portions -22 spaced awayfrom plate 3 as shown at 23. Channels 19 are connected with plenumchambers 6. Channels 18 are not connected with plenum chambers 6 but maysuitably be so connected if desired. Drains 25 and 26 are provided topermit removal of water and melted ice which may collect in the channelsand plenum chambers.

As shown in Figures 4 and 5 the portion of the device disposed alongsidethe horizontal edge of plate 3 may be made more simply. Bottom 30 andupwardly extending walls 31 and inwardly extending roof portions 32 maybe disposed around central partition to provide channels 33, the inneredges of roof portions 32 being disposed away from the surfaces of plate3 as shown at 35. Plenum chambers 3-6 may be generally coextensive withthe bottom of duct 7. Channels 33 open into plenum chambers 36. Drains37 and 38 are provided respectively to drain the plenum chambers andtrough portions of collected water and melted ice.

There is shown in Figure 6 an alternative installation of the deviceaccording to the invention which may be utilized if desired althoughmost of the advantages of the invention are sacrificed in such anarrangement. Blowers 40 pull cool air upward alongside the plate 3thence into trough portion 41, thence into plenum chambers 42 connectingtherewith, and thence through ducts 43. The cool air thus pulled intoblower 40 is blown out over the top of contents 10.

it may be seen that due to the tendency of hot air to rise, the air asit is heated by goods 10 will pass in a relatively direct path to trough41 rather than passing alongside the wails of plate 3, thus in effectshort-circuiting the refrigerating unit 3 and resulting in lessenedefliciency of the installation.

Thus it may be seen that the invention is broad in scope and is to belimited only by the claims.

Having thus disclosed my invention, I claim:

1. In a refrigerated compartment, the combination of a vertical flatplate cooling unit and an air collecting and blowing device comprisingan upwardly extending partition disposed with its upper edge near andparallel to a horizontal edge of said cooling plate, a floor portionextending outwardly from the bottom edge thereof and a wall portionextending upwardly from the outer edge of said floor portion adapted toconjointly define a channel adapted to receive air flowing verticallyalong a wall of said flat plate, a plenum chamber connected to one endof said channel and a duct connected to said plenum chamber.

2. In a refrigerated compartment, the combination of a vertical flatplate cooling unit and an air collecting and blowing device comprisingan upwardly extending partition disposed with its upper edge near andparallel to a horizontal edge of said cooling plate, floor portionsextending outwardly from said partition and wall portions extendingupwardly from said floor portions to define at least one channel on eachside of said partition, plenum chambers at each end of said partitionconnected with said channels and ducts connecting to said plenumchambers.

3. In a refrigerated compartment, the combination of a vertical flatplate cooling unit and an air collecting and blowing device comprisingan upwardly extending partition disposed with its upper edge near andparallel to a horizontal edge of said cooling plate, floor portionsextending outwardly from the bottom marginal edge of said partition oneach side thereof, wall portions extending upwardly from the outermarginal edges of said floor portions and roof portions extendinginwardly from the upper marginal edges of said wall portions, adapted todefine two channels, one on each side of said central partition, saidchannels adapted to receive air flowing vertically along the walls ofsaid flat plate, plenum chambers at the ends of said partition and ductsconnected to said plenum chambers.

4. ln a refrigerated compartment, the combination of a vertical flatplate cooling unit and an air collecting and blowing device comprisingan upwardly extending partition disposed with its upper edge near andparallel to a horizontal edge of said cooling plate, a floor portionextending outwardly from the bottom marginal edge of said partition oneach side thereof and wall portions extending upwardly from the outermarginal edges of said floor portion plenum chambers at the ends of saidpartition and the ducts connected to said plenum chambers, a secondfloor portion extending under said first floor portion and outwardlybeyond the edges thereof, wall portions extending upwardly from theouter edges of said second floor portion and roof portions extendinginwardly from the upper marginal edges of said outer wall portions, saidpartition, wall and roof portions adapted to together provide twochannels on each side of said central partition, said channels adaptedto receive air flowing vertically along the walls of said flat plate, atleast said outer channels openinginto said plenum chambers, and ductsopening into the tops of said plenum chambers.

5. In a refrigerated compartment, the combination of a vertical flatplate cooling unit and an air collecting and blowing device comprisingan upwardly extending partition disposed with its upper edge near andparallel to a horizontal edge of said cooling plate, at least onechannel on each side thereof defined by said partition, floor portions,wall portions extending upwardly from the outer marginal edges of saidfloor portions and roof portions extending inwardly from the uppermarginal edges of said wall portions, said channels opening into plenumchambers at each end of said partition, and ducts opening upward fromsaid plenum chambers.

6. In a refrigerated compartment, the combination of a vertical flatplate cooling unit and an air collecting and blowing device comprisingan upwardly extending partition disposed with its upper edge adjacent ahorizontal edge of said cooling plate, two channels on each side of saidpartition, each substantially defined by a floor portion substantiallyconnected to the bottom marginal edge of said central partition and bywall portions extending upwardly from said bottom portions, plenumchambers at each end of said central partition and ducts connected tosaid plenum chambers.

7. Apparatus comprising in combination the device of claim 1, means forwithdrawing air from at least one end of said-channel unit, means forconveying said air to an upper portion of side compartment and means forthere re-introducing said air into said compartment.

8. In a refrigerated compartment, the combination of a verticallydisposed flat plate cooling unit, channel means disposed along ahorizontal edge of said unit adapted to receive air flowing verticallyalong at least one side thereof, means for withdrawing such air from atleast one end of said channel unit, means for conveying said air to anupper portion of said compartment containing said unit and means forthere re-introducing said air into said compartment.

9. The device of claim 8 wherein two such channel means are provided.

10. The device of claim 8 wherein four such channel means are provided.

11. The device of claim 1 wherein said partition is adjacent to saidhorizontal edge.

12. The device of claim 2 wherein said partition is adjacent to saidhorizontal edge.

References Cited in the file of this patent UNITED STATES PATENTS StrassMay 9, 1933 Philipp Nov. 6, 1934

